How To fetch data from json for slider

问题

I am working on an image and text slider that shows images and text in slider using view pager. in this project text and images, the array is defined in the app itself. how can load these values from a JSON API?. instead of defining it i want to load these from an json file online. Please help.

My Adapter Code

public class SlideAdapter extends PagerAdapter {
    Context context;
    LayoutInflater inflater;

    // list of images
    public int[] lst_images = {
            R.drawable.image_1,
            R.drawable.image_2,
            R.drawable.image_3,
            R.drawable.image_4
    };
    // list of titles
    public String[] lst_title = {
            "COSMONAUT",
            "SATELITE",
            "GALAXY",
            "ROCKET"
    }   ;
    // list of descriptions
    public String[] lst_description = {
            "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,",
            "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,",
            "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,",
            "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,"
    };
    // list of background colors
    public int[]  lst_backgroundcolor = {
            Color.rgb(55,55,55),
            Color.rgb(239,85,85),
            Color.rgb(110,49,89),
            Color.rgb(1,188,212)
    };


    public SlideAdapter(Context context) {
        this.context = context;
    }

    @Override
    public int getCount() {
        return lst_title.length;
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return (view==(LinearLayout)object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        inflater = (LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
        View view = inflater.inflate(R.layout.slide,container,false);
        LinearLayout layoutslide = (LinearLayout) view.findViewById(R.id.slidelinearlayout);
        ImageView imgslide = (ImageView)  view.findViewById(R.id.slideimg);
        TextView txttitle= (TextView) view.findViewById(R.id.txttitle);
        TextView description = (TextView) view.findViewById(R.id.txtdescription);
        layoutslide.setBackgroundColor(lst_backgroundcolor[position]);
        imgslide.setImageResource(lst_images[position]);
        txttitle.setText(lst_title[position]);
        description.setText(lst_description[position]);
        container.addView(view);
        return view;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((LinearLayout)object);
    }
}

回答1:

Read this code, you pass a url to this method, and recive a response:

private static String makeHttpRequest(URL url) throws IOException {
        String jsonResponse = "";

        if (url == null) {
            return jsonResponse;
        }
        HttpURLConnection urlConnection = null;
        InputStream inputStream = null;
        try {
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setReadTimeout(10000 /* milliseconds */);
            urlConnection.setConnectTimeout(15000 /* milliseconds */);
            urlConnection.setRequestMethod("GET");
            urlConnection.connect();

            if (urlConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                inputStream = urlConnection.getInputStream();
                jsonResponse = readFromStream(inputStream);
            } else {
                Log.e(LOG_TAG, "Error response code: " + urlConnection.getResponseCode());
            }
        } catch (IOException e) {
            Log.e(LOG_TAG, "Problem retrieving the JSON results.", e);
        } finally {
            if (urlConnection != null) {
                urlConnection.disconnect();
            }
            if (inputStream != null) {
                inputStream.close();
            }
        }
        return jsonResponse;
    }

Then:

JSONObject baseJsonResponse = new JSONObject(jsonResponse);

JSONArray itemsArray = baseJsonResponse.getJSONArray("items");

来源：https://stackoverflow.com/questions/52052605/how-to-fetch-data-from-json-for-slider